Hydraulic system control means



July 19, 1938.

E. J. LATTN ER HYDRAULIC SYSTEM CONTROL MEANS Filed May 4', 1936 1 INVENTOR.

ENE/Q7 J. LA 7'7'N/? Patented July 19, 1938 UNITED STATES PATENT OFFICE 2,123,950 HYDRAULIC SYSTEM CONTROL MEANS Emert J. Lattner, Cedar Rapids, Iowa Application May 4, 1936, Serial No. 77,780

2 Claims. (01. 103-42) This invention relates to oil burners and has Figure 1 is a side elevational view of an oil particular relation to means for removing air burner as it appears installed and of the fuel from the fuel supply, pumping, and control supply tank and the control means for controlmeans of such burners, ling the flow of fuel .to the nozzle of the oil In setting up oil burners it is necessary to burner. remove air from the fuel supply means, from Figure 2 is a diagrammatic illustration showthe pumping means, and from the various coning the flow of oil from the supply tank to the duits employed for supplying fuel to the nozzle, nozzle of a burner, together with a view in secas it is otherwise difficult, if not impossible, for tion of one embodiment of my invention, and h the pump to pull the oil into the system. This Figure 3 is a view in section of a venting device 10 is particularly true when the supply tank is constructed according to one embodiment of my located below the level of the oil burner. Howv t n as itapp ars i p d in t never, I have discovered that if the return or ventional combination strainer," pump and conre-circulation line is vented to atmosphere to trol valve means of an oil burner.

permit the pump to drive air out of the system Referring now to the drawing, and more par- 15 and replace the air with liquid fuel, the air may ticularly to F gures 1 and 2 thereof, there is illusbe removed from the system and the vent then trated at Ill generally a fuel supply tank having closed to permit pumping the fuel to the nozzle. a filling p p H n v 'p pe 2 in c rd n e At the same time the return line beyond the with the usual construction.

- vent must be closed to prevent loss of vacuum A fuel supply line I3 is provided and the flow 20 during venting and opened when exhaustion of of fuel into this line is controlled by the shut-01f the trapped air has been completed. These valve I 4 at the supply tank Hi.- In operation the operations must be accomplished simultaneously fuel passes from thetank l0 through the valve andpracticany instantaneously, l4 and supply line l3 and into the strainer I6 It is, therefore, a general object of my inventhrough the shut-off valve IS. The fuel then 25 tion to provide means for starting the flow of pass r m he rainer I6 to the pump 11 and fuel oil to the nozzles of oil burners and to avoid into he n r l v lve Ill. The control valve l8. the dimculties, some of which are enumerated as here wn. is a two part valve in which the ab upper part l8a houses a. valve mechanism which It is another genera] obj ct of my ti n permits fuel to' flow through the nozzle (not 30 to provide, in an oil burner fuel supply system, shown) when fuel pressure of the order of forty. readily operable vent means to facilitate drivpounds is reached. The size of the op in m i frqm t system the nozzle varies in accordance with the heating It is another object of my invention to proap ty of t burner. t t e quantity of fl w vid i an 11 burner fuel p t means of oil from the nozzle is always considerably less 35 for venting the system to the atmosphere'and than the qua t y of flow from the P p at the same time closing oil the return line and The lower p rt a of the valve l8 houses anin another position of the control means to close other Valve mechanism Which becomes op t the vent to atmosphere and open the return line. under pressures of the order of one hundred 40 It is still another object of my invention to pounds to Permit 11 b returned or by-passed 40 provide venting means of the above character through a return line I9 to the strainer l8.

f which may be incorporated in the conventional However, there s Small p g 0 through strainer, pump, and control valve structure used s Valve 81? l times to p it a im ted flow mm 1 burners of fuel through the return line l9 even when the ot and further features and objects of t valve I8b is closed. The flow of fuel in the sys- 45 invention will be more apparent to those skilled tem of Figure 1 at the burner is diagrammatiin the art upon a consideration of the accomcally illustrated in Figure 2 butwith the addipanying drawing and following specifications, tion ofa venting device 2| constructed accordwherein is disclosed a single exemplary embodi- 8 t0 n eembodlmerit of my i v n, this ment, of th i ti with the understanding, venting device being located in the return line' H. 50 however, that such changes may be made therein Referring now to Figu e 2, oil from the supply as fall within the scope of the appendedclaims, tank passes through the line l3 intothe pump I! without departing from the spirit' of the and from the pump to one side of the valves Illa invention. a and lib corresponding to theupper andlower In said drawing: portion :91 the valve l8 oflllgure 1'. The pump I55 IT, for instance, may be so designed as to pump twenty-two gallons of fuel per hour. The nozzle at 22, for instance, may be set to pass only two gallons of fuel per hour. The valve I611, furthermore, may be set at a pressure of forty pounds and the valve |6b at one hundred pounds. It is obvious that if the pump I7 is started up with fuel in the system, the valve I811 will be opened first and fuel will flow at the rate of two gallons per hour from the nozzle 22. Since the pump l1 delivers twenty-two gallons of fuel per hour, pressure within the line 23 leading to the valves in and I6?) will soon exceed one hundred pounds and the excess oil will return to the line l9 and back into the strainer I6; A small portion of the fuelfrom the pump will be by-passed through the opening 20 of valve |6b at all times while the pump is pumping fuel.,

Now if air is trapped in the system illustrated in Figure 2, as it is when the system is first started or is started after a period of idleness, the pump i! probably will not draw the fuel into the system. The air within the system is merely driven by the pump through the opening 26 and return line l9 and back tothe intake of the pump to be re-circulated over and over in the same manner. By reason of the greater compressibility of the trapped air as compared to fuel it will.

pass through the small by-pass 26 before its pressure is raised sufficiently to raise the valve |8a from its seat to permit the trapped air to be driven through the nozzle.

If, however, the line I9 is vented to atmosphere and closed beyond the vent, the air will be pumped out of this system through this vent and oil will begin to flow out through the vent. If the return line I9 is then opened back to the line l3 and the vent closed, this flow of oil will continue and the oil will be pumped out of the nozzle 22 and excess oil flow back through the line l9 and into the supply line l3 to permit normal operation of the burner.

Preferred embodiments of my invention are 11- lustrated in Figures 2 and 3. In Figure 2 the venting device 2| is comprised of a cylinder 24 having a cylindrical chamber 26 therein. Fuel from the line l9 passes into the chamber 26 through an intake port 21 and may either pass out through the return line port 28 or out through a drain or vent port 29 in accordance with the position of the double faced valve 3|. In the normal position of the valve 3| the spring 22 lifts the lower valve face off of the seat 36 to thus open the return line port 28, the upper face 36 of the valve being held against the seat 91 by the pressure of the spring 22 to close the vent port 29. I

In order to vent air from the system and from the return line l9 the button 29 is depressed to thus open the vent port 29 and close the return line port 26. Air within the return line 9 is thus driven out into the atmosphere. When-oil begins to flow out of the vent port 29 the valve button 99 is released andthe vent port 29 is thus closed and return line port 26 opened to permit oil to be returned to the strainer I6.

Devices constructed according to my invention may be incorporated in combined strainer, pump and valve structures such as shown in Figure 3. The structure here shown is comprised of a strainer 4|, a gear pump, the teeth of which are indicated at 42, and a control valve structure indicated generally at 43. The pump is driven by means of the shaft 44 from an electric motor (not shown) or other. power source. While the structure shown in Figure 3 is a combination of several units, its operation generally is similar to the structure disclosed in Figures 1 and 2. Fuel enters into the strainer 4| through the port 66 and passes through the strainer and up into the main body of the structure through the channel 61 as indicated by the arrows. From the channel 61 the fuel passes into the spaces between the teeth of the gear pump and is discharged through the channel 66 into the chamber 49 beneath the valve piston 5|. A small by-pass 6!! permits a limited flow of fuel into the chamber 61 and channel 68 through the port 66 and chamber'66 and back into the channel 41 leading to the pump. As the pressure beneath the piston 6| builds up, the valve disc 66 of piston 6| is lifted from its seat and the fuel then flows through the channel 69 and through the nozzle of the burner.

In a given structure, for instance, the nozzle may only discharge on the order of two gallons of fuel per hour and the pump may pump as much as twenty-two gallons per hour, therefore the piston is raised still further until the port is uncovered. Fuel then passes from the chamber 49 through the port 64, around the wall of the cylinder, and out through'the port 66 and into the chamber 61. Fuel then flowsthrough the channel 56 to the cylindrical chamber 69 of a valve structure which is substantially the same as that shown in Figure 2.

If the double faced valve 6| is in the 'down position, as here shown, entrapped air may pass out through the discharge opening 62 and be discharged through the channel 69 in the valve button 64. Inasmuch as the valve face 6| closes the channel 66, the entrapped air cannot be returned to the channel 41. When fuel begins to flow from the channel or port 69 pressure on the button 64 is released, and the upper face of the double valve 6| closes the channels 62 and 63 by being seated by reason of the action of the spring 61 on the valve stem button 64, and thus opening the entrance to the conduit 66. Fuel oil then passes through the channel 66 into the chamber 68 and back into the channel 41 where it may be re-circulated.

It is apparent that the vent valve structure selectively either closes the by-pass or return channel and opens a vent to the atmosphere or closes the vent to the atmosphere and opens the by-pass channel. The device shown in Figure 3 operates in substantially the same manner as the device shown in Figures 1 and 2 and air is permitted to pass out of the system by depressing the venting valve until oil begins to flow from the valve. When oil begins to flow the venting valve is released and the oil will at once circulate through the system.

Although I have described a specific embodiment of my invention, it is apparent that modiiications thereof may be made by those skilled in the art. Such modifications may be made without departing from the spirit and scope of my invention as set forth in the appended claims.

I claim as my invention:

1. In an oil burner includinga fuel supply line, a pump, a return line from the discharge side of the pump to the intake side,-a' pressure valve for regulating the flow of fuel through the return line, the pressure valve having an air vent port leading from the discharge side of the pump to the return line, and a two seated vent valve in the return line adapted when in position on one seat to close of! the portion of the return line between the intake side of the pump and the valve and to vent to atmosphere the remaining portion or the return line between the valve and the discharge side of the pump, and when in position on the other seat to close 011 the vent to atmosphere and to open the return line.

2. In an oil burner including a fuel supply line. apump, a return line from the discharge side of the pump to the intake side, apressure valve for regulating the flow of fluid through the return line, the pressure valve having an air vent port from the high pressure side of the valve to the return line, a valve means for selectively venting the return line to atmosphere and closing the vent to atmosphere and opening the return line comprising a cylindrical member in the return line having an opening therethrough communicating with the atmosphere, a valve having the stem thereof extending within-the opening of the cylindrical member, the valve being adapted to seat on the cylindrical member to close the aforesaid opening therethrough and the valve also being adapted to seat in the return line to close off the return line between the seat and the intake side of the pump, a spring on the valve stem for keeping the valve normally seated on the aforementioned cylindrical member, and a push button on the valve stem adapted to be manually depressed to seat the valve in the return line for venting the return line to atmosphere.

EMERT J. LA'I'INER. 

